Blockchain for beginners: build certificate registration DApp

What wecoverWe briefly cover the philosophy of the blockchain and Ethereum. Then we will explain how blockchains work, what is Decentralized App and how smart contract communicates with DAppWe setup the easy development environment, including tools that can be used with minimum stepsAnd the biggest part of the course is dedicated to guiding you through a simple Decentralized AppSome of the keyword definition: Blockchain is a growing list of digital pieces of information which are linked using cryptography. It is an open, distributed ledger that can record transactions between two parties efficiently and also in a verifiable and permanent way. Decentralized applications (dApps) are applications that run on blockchain rather than a database. Smart contract is defined as pieces of computer code that self-execute when predetermined conditions are fulfilled. The results of the transaction will be written onto a distributed ledger or blockchain. We covered the following concept: EthereumAccountGasSmart ContractDecentralized AppBlockchainBitcoinSolidityWeb3. jsRopsten TestnetWhat tools and libraries are used?Ethereum The Metamask Chrome extensionThe Solidity smart contract language (0.5.0)The Web3. js(Web3 1.0.0)The Ganache Ethereum node emulatorGithubVisual Studio Code (text editor)The Ropsten test networkAll our codes are stored in Github and the solidity code will be stored as. sol file. Lesson 2 unit 1: @hashcademy-> choose certificate dapp ->choose branch masterLesson 2 unit 2: @hashcademy-> choose certificate dapp ->before modify javascript: choose branch 1a, after modify javascript: choose branch 2Lesson 2 unit 3: @hashcademy-> choose certificate dapp ->choose branch 3Lesson 2 unit 4: @hashcademy-> choose certificate dapp ->choose branch 4Lesson 2 unit 5: @hashcademy-> choose certificate dapp ->choose branch 5